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IS IT a worm? Is it a strand of spaghetti? No, it’s the world’s smallest snake.

Blair Hedges, an evolutionary biologist at Pennsylvania State University in University Park, discovered the 10-centimetre-long Leptotyphlops carlae on the island of Barbados. It belongs to a family of threadsnakes that look like earthworms and have lower jaws that work like rakes to drag ant and termite larvae into their mouths (Zootaxa, vol 1841, p 1).

Hedges has something of a knack for finding tiny critters. In 2001, he made headlines by discovering the world’s smallest gecko. And in 1993, he was part of the team that stumbled across the world’s smallest frog.

Islands are ideal places to find very large or very small species, Hedges says, because island forms can claim ecological niches that would already be occupied by other species on the mainland, where diversity is higher.

A NEW approach to measuring glacier behaviour can keep track of the rapidly changing erosion of ice in south-east Greenland.

Earlier studies focused on two large, rapidly thinning glaciers, but these actually contribute relatively little to total ice loss. Satellite measurements of the island’s gravitational field imply a much greater loss than the large glaciers alone can account for.

Now a team led by Ted Scambos of the University of Colorado in Boulder has resolved the disparity by looking at a wider range of glaciers. They used laser altimetry to measure the thinning of inland ice, plus satellite images that show changes at the margins of the ice sheet. Overall, they found that the region is losing more than 100 cubic kilometres of ice a year.

TOO busy to go for a run? One day you might be able to build endurance just by popping a pill.

Ronald Evans of the Salk Institute in La Jolla, California, has discovered two compounds that turn ordinary mice into long-distance runners, and that one of them works even if the mice don’t exercise beforehand. If they have the same effect in people, the compounds may one day be used to fight obesity, by increasing fat metabolism. Evans fears, though, that they could be abused by athletes.

His team trained mice on a treadmill and for half of them paired training with doses of a compound, WG1516. This activates a gene that causes cells to burn extra fat and make more mitochondria – the cell’s power-producing structures. When tested on endurance, those that had taken the compound jogged longer and further than the mice that did not (Cell, DOI&colon; 10.1016/j.cell.2008.06.051). Their muscles also boasted more “slow-twitch” fibres, which are important for endurance.

In a second experiment, mice with no prior treadmill training were injected with a different compound, AICAR. This encourages the production of muscle fuel, and enabled mice to run about 44 per cent longer than untreated mice. “This is the couch potato experiment,” says Evans.

SMOKING hash or marijuana may not be the healthiest way to do it, but taking substances similar to those found in cannabis might one day help to treat colon cancer.

Raymond DuBois and colleagues at the University of Texas, Houston, discovered that a key receptor for cannabinoids – compounds similar to the active ingredient of cannabis – is turned off in most types of human colon cancer cells. Similarly, mice genetically engineered to develop colon tumours developed more of them if the receptor, called CB1, was knocked out (Cancer Research, DOI&colon; 10.1158/0008-5472.CAN-08-0896). What’s more, tumours shrank when the genetically engineered mice were injected with a cannabinoid.

One suggestion is that lack of CB1 encourages tumour growth because the receptor normally interacts with cannabinoids made by the body to prompt cells to die. This opens up a possible two-step treatment for colon cancer. First, switch CB1 back on using decitibine, a drug already approved for use in humans which DuBois and his team showed stops blockage of the receptor in human colon cancer cells. Then give the patient cannabinoids to activate CB1.

The research also casts a shadow on the weight-loss drug rimonabant. The drug suppresses appetite by blocking CB1, which is involved in hunger as well as tumour growth. DuBois suggests that anyone on the drug be screened for colon cancer.

GIANT stars did indeed illuminate the early universe. Astronomers have wondered whether the first coalescing gas clouds would have been unstable and fragmented to create only small primordial stars. Now the most complete simulation yet of star formation after the big bang suggests this did not happen.

In the model, created by a team led by Naoki Yoshida of Nagoya University in Japan, huge stars coalesce about 300 million years after the big bang. At first, patches of hydrogen and helium gas collapse under gravity and slowly warm up. Hydrogen atoms then form molecules, which radiate away the building heat, reducing thermal pressure and allowing the cloud to collapse further to form a protostar.

“The first object to be formed in the universe is a very tiny protostar with mass just 1 per cent of the sun,” says Yoshida. That star then acts as a seed, quickly growing to about 100 times the mass of the sun. After a brilliant million-year lifetime, such a star might explode as a supernova, scattering heavy elements and triggering more star formation.

WHAT is the sound of dots moving? Most can’t say, but for those with a newly identified form of synaesthesia, “hearing” sights is the most natural thing in the world – and may make it easier for synaesthetes to recognise visual patterns.

Melissa Saenz at the California Institute of Technology in Pasadena was tipped off when a grad student saw her screensaver and asked&colon; “Does anyone else hear that?” His experience had the hallmarks of synaesthesia, in which stimulation of one sensory pathway creates an experience in another. When Saenz circulated the “noisy” image via email, three more synaesthetes came forward.

Ordinarily, people are better at recognising patterns if they are auditory rather than visual. To see if hearing-sight synaesthesia might make people better at recognising visual patterns, Saenz and collaborator Christof Koch asked the synaesthetes and a group of controls to listen to or watch pairs of sequences in the same modality and say whether they were identical; half were and half weren’t. Both groups were about 85 per cent accurate on the sound patterns, but while controls got only 55 per cent of the visual rhythms right, synaesthetes remained steady at 85 – and they reported later that they were indeed hearing the flashes as well as seeing them (Current Biology, DOI&colon; 10.1016/j.cub.2008.06.014).

“You can’t fake being better,” says neuroscientist Jamie Ward at the University of Sussex, UK. Finding new types of synaesthesia is not uncommon, he says, and they often confer an advantage.

The Human Brain – With one hundred billion nerve cells, the complexity is mind-boggling. Learn more in our cutting edge special report.

IT’S not just the sphere of culture that has an east-west divide. The Earth’s inner core of solid iron also behaves differently in each hemisphere, transmitting seismic waves faster in the eastern side than in the west.

The phenomenon has baffled scientists, but now numerical simulations developed by Julien Aubert of the French national research centre’s Institute of Geophysics in Paris and his team suggest that the anomaly may be due to subterranean “cyclones” found in parts of the liquid iron outer core.

These swirling cyclones drag cooler material from the top of the outer core right down to the bottom, where iron is gradually crystallising onto the solid inner core. This cooling causes crystals to form more quickly and with random alignments. That makes the material stronger, which in turn means it is able to carry seismic waves more quickly.

Aubert’s work indicates that for the past 300 million years most of these iron cyclones will have been found below Asia, so most of the cooling effect will have been in the eastern hemisphere. Over that time, the inner core has grown by about 100 kilometres, and on the eastern side of the core that layer should have formed from the fast-transmission crystals.

TRACES of milk found in 9000-year-old ceramic pot fragments have pushed back the earliest known consumption of animal milk by people by a millennium.

Cattle, sheep and goats were domesticated in the Near East about 10,000 years ago, but many archaeologists believe people used only their meat and hides at first, with secondary uses such as wool, power and milk coming much later.

Richard Evershed at the University of Bristol, UK, and his colleagues collected 2225 pottery fragments from the Near East, dating from the seventh to fifth millennia BC. By measuring carbon isotope ratios in organic residues on the shards, they found that many – especially very old ones from north-west Anatolia, now Turkey – had contained milk (Nature, DOI&colon; 10.1038/nature07180).

Other studies indicate that the people of the era lacked the enzymes to digest animal milk in its fresh form, but if it had been stored in the form of cheese or butter they would have been able to consume it, the authors say.

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In order to milk animals, people must have kept them nearby and closely controlled. This implies that early pastoralists had tighter social organisation than previously thought, says Margie Burton of the San Diego Archaeological Center in California.

Human Evolution – Follow the incredible story in our comprehensive special report.